Most Important Selected Qs for JEE AdvancedPhysicsWork, Power and Energy
A uniform rope of line mass density and length is coiled on a smooth horizontal surface. One end is pulled up by an external agent with constant vertical velocity v. Choose the correct option(s).
Options
- APower developed by external agent as a function of x is P= x g v
- BPower developed by external agent as a function of x is P= ( v^2+ x g ) v
- CEnergy lost during the complete lift of the rope is zero.
- DEnergy lost during the complete lift of the rope is v^2 2 .
Correct answer
D. Energy lost during the complete lift of the rope is v^2 2 .
Step-by-step solution
aligned & F applied by external agent = Weight + thrust force = x g+ v^2 & Energy lost in the complete lift =W_F- K . E .- U= v^2 2 aligned